public class MatchingServiceImpl implements MatchingService {
  private static final Logger log = LoggerFactory.getLogger(MatchingServiceImpl.class);
  @Autowired
  private QuoteService quoteService;
  ...
  public MatchingResult matching(MatchingOrder buyOrder, MatchingOrder sellOrder) {
    int currentPrice = quoteService.getCurrentPriceByProduct(buyOrder.getProductCode());
    MatchingResult result = new MatchingResult();
    if (sellOrder != null && buyOrder != null &&
        sellOrder.getPrice() <= buyOrder.getPrice()) {
    ...
  }
}

public class MatchingServiceImplTest extends MockitoBasedTest {
  /**
   * 被@Mock標(biāo)注的對(duì)象會(huì)自動(dòng)注入到被@InjectMocks標(biāo)注的對(duì)象中
   */
  @Mock
  private QuoteService quoteService;
  /**
   * <pre>
   * 被測(cè)對(duì)象，用@InjectMocks標(biāo)注，那些被@mock標(biāo)注的對(duì)象就會(huì)自動(dòng)注入其中。
   * 另一個(gè)注意點(diǎn)是這里的MatchingServiceImpl是直接new出來(lái)(Mockito 1.9版本后不new也可以)，而不是通過spring容器注入的。因?yàn)檫@里我不需要從spring容器中
   * 獲得其他依賴，不需要database ，redis ，zookeeper，mq，啥都不依賴，所以直接new
   * </pre>
   */
  @InjectMocks
  private MatchingServiceImpl matchingService = new MatchingServiceImpl();
  @Test
  public void testMatching_SuccessWhenCurrentPriceBetweenBuyPriceAndSellPrice() {
    MatchingOrder buyOrder = new MatchingOrder();
    buyOrder.setPrice(1000);
    buyOrder.setCount(23);
    MatchingOrder sellOrder = new MatchingOrder();
    sellOrder.setPrice(800);
    sellOrder.setCount(20);
    // 方法打樁(Method stubbing)
    // when(x).thenReturn(y) ：當(dāng)指定方法被調(diào)用時(shí)返回指定值
    Mockito.when(quoteService.getCurrentPriceByProduct(Mockito.anyString())).thenReturn(900);
    MatchingResult result = matchingService.matching(buyOrder, sellOrder);
    org.junit.Assert.assertEquals(true, result.isSuccess());// 斷言撮合是否成功
    org.junit.Assert.assertEquals(20, result.getTradeCount());// 斷言成交數(shù)量
    org.junit.Assert.assertEquals(900, result.getTradePrice()); // 斷言最新報(bào)價(jià)是否符合預(yù)期
  }

protected void startBuyProcess(MatchingOrder buyOrder, boolean waitForMatching) {
    while (true) {
      //對(duì)手方最優(yōu)價(jià)
      MatchingOrder topSellOrder = getTopSellOrder(buyOrder.getProductCode());
      MatchingResult matchingResult = matching(buyOrder,topSellOrder);
      if(matchingResult.isSuccess()) {
        doMatchingSuccess(buyOrder,topSellOrder,matchingResult,MatchingType.BUY);
        if(buyOrder.getCount() <= 0) {
          break;
        }
      }else {
        if(waitForMatching) {
          //加入待撮合隊(duì)列
          addToMatchingBuy(buyOrder);
        }else {
          //撤單
          sendCancleMsg(buyOrder);
        }
        break;
      }
    }
  }

/**
   *
   * 測(cè)試StartBuyProcess方法在撮合成功后的處理是否符合預(yù)期，即測(cè)試startBuyProcess方法進(jìn)入下面這個(gè)判斷分支后的行為
   * {@link MatchingServiceImpl#startBuyProcess(MatchingOrder, boolean)}
   *
   * <pre>
   * if (matchingResult.isSuccess()) {
   *
   *   doMatchingSuccess(buyOrder, topSellOrder, matchingResult, MatchingType.BUY);
   *
   *   if (buyOrder.getCount() &lt;= 0) {
   *     break;
   *   }
   * }
   * </pre>
   *
   */
  @Test
  public void testStartBuyProcess_InCaseOfMatchingSuccess() {
    MatchingOrder buyOrder = new MatchingOrder();
    buyOrder.setPrice(700);
    buyOrder.setCount(23);
    // 用Mockito.spy()對(duì)matchingService進(jìn)行部分打樁
    matchingService = Mockito.spy(matchingService);
    MatchingResult firstMatchingResult = new MatchingResult();
    firstMatchingResult.setSuccess(true);
    firstMatchingResult.setTradeCount(20);
    MatchingResult secondMatchingResult = new MatchingResult();
    secondMatchingResult.setSuccess(false);
    // doReturn(x).when(obj).method() 對(duì)方法打樁，打樁后，程序執(zhí)行這些方法時(shí)將按照預(yù)期返回指定值，未被打樁的方法將真實(shí)執(zhí)行
    // 兩個(gè)doReturn表示第一次調(diào)用matchingService.matching時(shí)返回firstMatchingResult，第二次調(diào)用返回secondMatchingResult
    // 因?yàn)閟tartBuyProcess里有個(gè)while循壞，可能會(huì)多次執(zhí)行matching方法
    Mockito.doReturn(firstMatchingResult).doReturn(secondMatchingResult).when(matchingService)
        .matching(Mockito.any(MatchingOrder.class), Mockito.any(MatchingOrder.class));
    MatchingOrder sellOrder = new MatchingOrder();
    sellOrder.setPrice(600);
    sellOrder.setCount(20);
    // 對(duì)getTopSellOrder方法打樁
    Mockito.doReturn(sellOrder).when(matchingService).getTopSellOrder(Mockito.anyString());
    // 對(duì)外部依賴jedis的方法進(jìn)行打樁
    Mockito.when(jedisClient.incrBy(Mockito.anyString(), Mockito.anyLong())).thenReturn(0L);
    // startBuyProcess是被測(cè)函數(shù)，不打樁，會(huì)真實(shí)執(zhí)行
    matchingService.startBuyProcess(buyOrder, true);
    // 后面的校驗(yàn)和斷言是測(cè)試doMatchingSuccess方法的行為的，這也是這個(gè)測(cè)試的目的
    // verify可用來(lái)校驗(yàn)，某個(gè)類的方法被執(zhí)行過多少次，這里是校驗(yàn)jedisClient.zremFirst是否被執(zhí)行過1次
    Mockito.verify(jedisClient, Mockito.times(1)).zremFirst(Mockito.anyString());
    org.junit.Assert.assertEquals(3, buyOrder.getCount());
    org.junit.Assert.assertEquals(0, sellOrder.getCount());
  }

<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.11</version>
  <scope>test</scope>
</dependency>

<dependency>
  <groupId>org.mockito</groupId>
  <artifactId>mockito-all</artifactId>
  <version>1.10.19</version>
  <scope>test</scope>
</dependency>
<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-test</artifactId>
  <version>4.2.5.RELEASE</version>
  <scope>test</scope>
</dependency>

@RunWith(SpringJUnit4ClassRunner.class)
@SpringApplicationConfiguration(classes = TestApplication.class)
public abstract class MockitoBasedTest {
  @Before
  public void setUp() throws Exception {
    // 初始化測(cè)試用例類中由Mockito的注解標(biāo)注的所有模擬對(duì)象
    MockitoAnnotations.initMocks(this);
  }
}
// 其他測(cè)試類繼承MockitoBasedTest